During the refining period, vibrations occur which are caused by the reactions in the metal bath. The vibrations are transmitted to the brick lining and wall of the converter vessel. In case the converter vessel is supported by an annular support resting in a tilting stand by means of pivot pins, the vibrations travel via the supporting elements between converter wall and annular support, and via annular support to the pivot pins, and finally to the pivot pin gear wheel and gear wheel pinions, which transmit the drive power to the pivot pin gear wheel. The vibrations are particularly detrimental at the point of tooth engagement of the pivot pin gear wheel and the drive pinions. The apparatus of the invention serves to eliminate the destructive effects of the vibrations on the converter tilting gear.
It is a known fact from bottom-blast Thomas converters to form the converter tilting gear of two hydraulic plunger gears whose axes run parallel, perpendicular and tangential relative to the pivot pin gear wheel. Attached to the piston rods are racks which transmit the motive power to the pivot pin gear wheel. Such type of apparatus has already been utilized to lock the converter tilting gear. For locking in place, the racks are moved in countermovement so that the play between rack teeth and pivot pin gear wheel is compensated for. Modern converter tilting gears consist of gears slipped onto the converter pivot pin in "flying" or cantilevered fashion, and of a torque support attached to the gear box, such torque support catching the restoring moment or play of the entire gear arrangement in a stationary location. This type of gear is, therefore, locked in principle only by counterrotation of pinions arranged in pairs versus the pivot pin gear wheel. In the tilting position, the converter swiveling around the pivot pin axis is locked by means of air cooled arresting brakes.
Furthermore, it has been disclosed in German Pat. No. 2,554,912 to provide one of the pinions with an additional gear which is engaged only when the coordinated arresting brake has been disengaged, and the arresting brakes of the remaining pinions have retracted. This structure is based on the concept of reciprocally bracing only two tooth engagement pairs out of several. However, this still leaves the teeth of the remaining pinions, which are not completely engaged, subject to deterioration caused by vibrations.
The present invention is based on the task of achieving bracing of all pinions which are positioned against the pivot pin gear wheel, even to the extent of providing for existing faults in tooth division and similar deviations from theoretical data. This is done by coordinating each pinion, in addition to the arresting brake, with its own auxiliary swivel gear, and by synchronously driving all auxiliary swivel gears in conjunction with overlay gears, while arresting brakes are locked, and in conjunction with a power introduction in an intermediary shaft of a serial gear, while arresting brakes are briefly released, whereby the swivel gears are connected to either one common energy source or to a separate energy source, with each supplied by one common energy accumulator. This ensures adherence of all engaged pinion teeth to the counter-teeth of the pivot pin gear wheel. This eliminates vibration of the teeth on a large scale, which also eliminates knocking of individual teeth. Thus, the risk of vibrations causing damages in the gear is considerably reduced.
The invention may be realized with electrical, pneumatic as well as hydraulic means. Based on hydraulics, the invention takes the form of swivel gears consisting of hydraulically charged thrust engines (reversible hydraulic cylinders) connected, via pressure lines. to one common, or several individual, hydraulic pressure reservoirs, whose pressure is regulated. Identical torque can thus be made available to each pinion at the pinion shaft. In case there are faults in division, differences in tooth width, or similar manufacturing defects affecting contact of the teeth with each other, tension in the elastic area of bending stress may be increased, so that differential tension occurs at the teeth, and minor manufacturing defects are compensated for.
The degree of pressure in the pressure medium may be controlled in that the pressure reservoir or reservoirs connected to a pump may be continuously regulated for a constant pressure by means of pressure switches. This pressure control system is of particular advantage as pressure must be maintained only during the blasting period, i.e. for approximately 15 to 20 minutes. Based on the fact that the use of thrust engines in lieu of rotating motors represents a simplificaton of the auxiliary swivel gear in view of the current technical status, it is also favorable that each thrust engine consists of piston cylinder gears whose cylinder box is flexibly supported at the gear box of the pivot pin gear wheel, and whose piston rod may be disengaged and engaged at the shaft of a serial gear for each of the pinions.
The connection between the thrust engine and clutch can be done so that the piston rod of the thrust engine is indirectly connected to the serial gear via a lever hinged at the piston rod, such lever being attached non-rotatably with one part of the clutch. The clutch should be by-passed, however, if the invention further provides that the piston rod of the thrust engine is connected, via a hinged lever, to the serial gear shaft leading out of the gear box, such serial gear shaft pertaining to the sun wheel of a serial gear designed as planetary gear. Furthermore, the cylinder box is attached at the box of the serial gear, and the motor shaft of the planetary unit is connected to the pinion of the pivot pin gear wheel by means of several gear stages.
Another simplification permitting the pinion a relative movement versus the pivot pin gear wheel results from the fact that the thrust engine, consisting of a piston cylinder gear, is flexibly attached with its cylinder box and/or piston rod at the gear box of the pivot pin gear wheel on one side, and on the other side it is flexibly attached to the gear box of the serial gear for the pinion, and that the gear box for the pivot pin gear wheel and/or gear box for the pinion can be tilted at least the equivalent of the existing play. This tilting is achieved, in accordance with the invention by arranging the serial gear with gear box in swinging fashion around the shaft of the pinion in the gear box of the pivot pin gear wheel.
In order to control vibrations occurring during the refining process in the metal bath, which travel through the brick lining, vessel wall, supporting elements, annular support, pivot pin up to the gear, and which practically cannot be prevented, it is necessary to introduce a damping link. This link is provided to absorb the vibrations. In accordance with the present invention, such damping link is, preferably, arranged locally so that in at least one link of the power transmission between auxiliary swivel gear and pinion, one vibration absorber is placed. In this spot, it is very easy to maintain and/or exchange the vibration absorber.
If the invention is realized exclusively with hydraulic or pneumatic thrust engines, there may be different travel paths of pistons and/or cylinders. These differences are compensated for by coordinating each thrust engine with a stop, whose movement is limited by a counter-stop which is stationary and adjustable to different travel paths.